Vintage Marshall Electronics Stethoscope and Aneroid Sphygmo (Blood Pressure)

Vintage Marshall Electronics Stethoscope and Aneroid Sphygmo (Blood Pressure). These items both appear to be in working order. I don't know how to use the blood pressure cuff, but I imitated what they do at the doctor's office and it behaved as I would expect...I just don't know the accuracy. For the Stethoscope, it also appears to work as expected (I could listen to my own heart.) The blue tubing on the stethoscope appears a bit tacky to the touch, but it may just need a bit of soap and water to clean. There doesn't appear to be any damanage to either item and both come in the original boxes. The boxes are solid, but do have wear around the edges from handling.